1. Field of the Invention
The present invention relates generally to a paint system for stripping or otherwise removing one or more layers of cured coats of paint, varnish or the like from a surface which system utilizes environmentally safe chemicals that have an efficient rheology identical to that of paint. The present invention, more particularly, relates to such a system which has safer effective chemicals and greatly improved rheology to ensure even application.
It is well known in the art to remove or otherwise strip cured coatings of paint, varnish or the like chemically from surfaces by treating the coated surfaces with a stripper system or composition that includes volatile chlorinated hydrocarbons, such as methylene chloride, or strong alkaline, such as sodium hydroxide. Commercially available paint stripper compositions contain these ingredients or chemicals. While such ingredients provide effective paint stripping capabilities, their use presents problems for the environment.
Specifically, methylene chloride is a suspected carcingenic. Therefore, full protective clothing and breathing equipment is recommended when methylene chloride is used, especially in a confined area. Furthermore, the rapid evaporation of methylene chloride limits the dwell time, and thus the number of coats that can be removed in one application. Accordingly, this increases the amount of labor and material costs when removing multiple coats of paint. Also, certain surfaces, such as fiber glass, can be damaged by using paint removers containing methylene chloride.
It is believed that heretofore all types of chemical paint removers suffer from one serious drawback, that is the inability of the user to ensure an exactly even coating of the stripper composition so essential to an even paint strip, since an uneven strip requires further applications to remove all the paint.
While sodium hydroxide in a paint remover composition does not produce toxic fumes, it can cause serious burns on unprotected skin. Also, sodium hydroxide needs to be used in an alkaline water based system, therefore it will darken certain woods and, in addition, treated surfaces will need neutralizing.
2. Description of the Prior Art
U.S. Pat. No. 4,579,627 to Michael I. D. Brailsford, the inventor of the present invention, issued on Apr. 1, 1986. This patent, which is directed to a Paste Stripper System for Surfaces, provides a stripper composition system which uses methylene chloride in an amount between about 15 to 85 percent by weight of the total stripper composition. This patent also provides for the use of cover means to remove stripped paint.
U.S. Pat. No. 3,950,185 to Mitsuo Toyama, et al., issued on Apr. 13, 1976 and is titled Film Removing Compositions. This patent is directed to compositions which include at least one halogenated hydrocarbon solvent selected from a group including methylene chloride.
U.S. Pat. No. 4,426,250 also to Michael I.D. Brailsford, the inventor of the present invention, issued on Jan. 17, 1984. This patent, which is titled Stripper System for Surfaces, provides a stripper composition system which includes a one alkaline material, such as sodium hydroxide.
U.S. Pat. No. 1,581,413 to Raymond M. Yoakam, which issued on Apr. 20, 1926, is titled Paint and Varnish Removing Composition. This patent is directed to a composition for removing paint and varnish which composition contains eleven and one-eight ounces of sodium hydroxide.
There is commercially available from 3M a product called "Safest Stripper" for removing paint or vanish. This product includes a dibasic ester and aluminum silicate which is not found in the present system. Further, this product does not contain the N-Methyl-2-Pyrrolidone of the present system.